Downstream of oncogenic signaling, TIMELESS is constitutively overexpressed in multiple types of cancer and required for increased cancer cell proliferation. TIMELESS depletion increases γH2AX, a marker of DNA damage, and triggers downstream G2/M arrest via increased CHK1 and CDK1 phosphorylation. Wee1 or CHK1 inhibition in combination with TIMELESS depletion demonstrates at least additive effects suggesting this combination may be efficacious for the treatment of cancer.

WDR5 is overexpressed, and WDR5 depletion reduces cell viability in colon cancer cells by reducing H3K4Me3 and increasing γH2AX, which further sensitizes cells to radiation-induced DNA damage. WDR5 inhibition also reduces colon cancer cell viability, but less so than WDR5 depletion.

The catalytic, kinase-containing a2 subunit isoform of AMPK is expressed at variable levels in colon cancer cells and is selectively required for colon cancer cell survival suggesting that AMPK kinase inhibition may be a useful component of cancer therapeutic strategies. FUSION identified 5´-hydroxy-staurosporine as a competitive inhibitor of AMPK that is selectively toxic to colon cancer cells.

Our results demonstrate the ability of FUSION to reveal functional similarities between genes, identify novel inhibitors, and expose oncogene-induced changes in cancer that promote proliferation and survival, but may also leave cancer cells vulnerable to targeted therapies.